Middle support broken!

izau3138

New member
I recently inherited a 55 gallon tank and the middle support is broken. Can I order a new complete top piece from All-Glass or can I use some acrylic piece. I am having a hard time understanding the mechanics of the brace. Help??
 
The brace helps hold the two sides of the tank in as they naturally want to bow out in the middle (due to the water). You do want to fix/replace it as it is there for a reason. If they bow too far they may break or split a seam.

I've not fixed a brace on an all-glass tank, so not much help there. The big tank fix of using silicon and a piece of glass seems like overkill, but it would work. I don't know if you could get a good bond between the plastic and a sheet of acrylic, but it might work if you had some mechanical connection (screws).

I'd first call All-glass or your LFS and see how much a new top piece is.
 
You can also use a piece of acrylic. Cut a piece about as wide as the original brace. Drill a hole in it and the edges of the tank where the original brace is. (You can cut most of the brace out, just leave enough to drill a hole for your new brace). Then use nylon screws to screw each end of it to the remaining piece at the edge of the original brace. The good thing about this is that it won't obstruct the light either.
 
<a href=showthread.php?s=&postid=8705153#post8705153 target=_blank>Originally posted</a> by azmorpheus
Most likely the cheapest best way to fix it would be to silicone a piece of glass in. $15 the most.

I have heard about this and I always wonder how it works. Won't the silicone just stretch as the tank bows and eventually pull apart?
 
Not too long ago I saw a thread here on RC which listed a link to a company that sold replacement frames. They were very reasonably priced.

I'm at work now and I saved it as a favorite at home. I'll try and find it when I get home and paste the link ASAP.

If you want to just fix the break here is a drawing as to how.

BrokenFrame-1.gif
 
Here is a low tek solution. build a piece of wood in the shape of a u. This is enough to hold the two glass pieces in proximity. Certainly not the most formal fix, but it will work. In fact you could make it part of your canopy. Just an idea.
 
<a href=showthread.php?s=&postid=8705843#post8705843 target=_blank>Originally posted</a> by kelley_mc
I have heard about this and I always wonder how it works. Won't the silicone just stretch as the tank bows and eventually pull apart?

Wouldnt the rest of the silicon on the tank do the same thing normally?
 
The silcone on a tank itself is all supported by the bracing on the perimeter of the tank. There is nowhere for the glass to move. If someone just silicones a piece of glass from the front to the back where the brace used to be, what keeps the silicone from stretching? My assuption is that it won't hold it from bowing. I have read that people do this, I just don't get how it would hold.
 
I also have an old Aga 55 tank this is the original design with no center brace 48" x 12". Definitely contact the manufacturer to see if you really need the brace
 
Once the silicone cures it does not stretch. If it did then eveyones glass tank would fall apart, even if you have the plastic braces. I had to replace the center brace on my tank a while ago and the orginal brace was glass sliliconed in. Silicone works very well as a bonding agent for glass. I still think your best bet in fixing the brace would be to get a strip of glass that is about 3" wide and the same thickness as the tank and bond it into place with silicone. Just make sure you allow it to cure for at least 24hrs. The silicone has a pretty high tensile strength once it cures and will not flex or stretch. Plus by fixing it this way you will not block as much light as the plastic did.
 
Wow you guys have way more faith in silicone than I do. I would never trust silicone and a piece of glass to hold the broken plastic brace together. That’s just me.

One day I got it in my mind that the center brace was something that needed to GO ... just as I cut it I about $h1T myself as the completely full tank instantly sprung quite a bit.

My wife and I quickly clamped the top of the tank to hold it back into its original position until we fixed it.
 
Your bonding the glass with silicone to the glass of the tank. Then after it cures you cut the broken plastic center brace out of the way. I dont understand why everyone is affraid of silicone. This is what they use to put our tanks together.
 
Here’s the link I promised to the plastic frames:
http://glasscages.com/?sAction=ViewCat&lCatID=43

azmorpheus, I understand what you're saying now … glass to glass. I misunderstood.

Still I trust the plastic frame more than I would trust silicone … me personally. I’ve seen where some have made some BIG all glass tanks using nothing but silicone to hold it all together 100%. I would never do that myself, but I’ve seen it done.

My personal outlook on glass aquariums is that they should all use a frame to ensure it is all held together on the top and the bottom. Silicone provides the seal at the seams. Yes silicone can be some tough stuff, but I’ve seen silicone fail even though the frame was in tip top shape. I’d hate to have not had a frame when the silicone went like it did.
 
<a href=showthread.php?s=&postid=8710014#post8710014 target=_blank>Originally posted</a> by RandyStacyE
Still I trust the plastic frame more than I would trust silicone … me personally. I’ve seen where some have made some BIG all glass tanks using nothing but silicone to hold it all together 100%. I would never do that myself, but I’ve seen it done.

My personal outlook on glass aquariums is that they should all use a frame to ensure it is all held together on the top and the bottom. Silicone provides the seal at the seams. Yes silicone can be some tough stuff, but I’ve seen silicone fail even though the frame was in tip top shape. I’d hate to have not had a frame when the silicone went like it did.

You are not alone... A typical tank uses silicone to prevent leaks between the glass pieces. I agree with RandyStacyE that most of the structural support is from the frames.

I am not saying it can't be done. I just wouldn't trust it. :D
 
The silicone to glass bond happens at a molecular (or maybe atomic ... don't remember right this second and it's late) and is incredibly strong. I suspect you could read a great deal about it on google, as its an interesting phenomenon.

The only glass tanks made commercially right now that don't rely on silicone for the all their strength are very large customs (8'x8'x30" or larger, which use welded steel). The frames on most tanks are there to protect the glass from point pressure sources, not support water.

To use a glass cross brace you do have to attach the glass to the tank directly tank not the plastic frame as that bond would be very weak.
A glass cross brace will be the strongest suggested this far (overkill), followed by a replacement frame, the mechanical patch and then the wood brace. For this size tank I would think any of the first 3 would be fine.
 
I don’t mean to get mixed up in another RC argument, but I just don’t buy into it. If silicone was reliable in the terms to meet structural integrity, then all glass aquarium manufacturers would not use plastic frames. They simply wouldn’t use them. All companies that manufacture a product at a certain level usually are insured; have to answer to be responsible to a manufacturer’s warranty, or a certain amount of accountability.

“Frames” in general are there for a reason, I’m not a structural or a mechanical engineer or anything, but I can tell you with absolute certainty that silicone is not a structural adhesive, but more a temporary maintenance product. In other words silicone is not a lifetime /permanent adhesive.

I wanted to stay away from such a debate, but izau3138 I just feel compelled to tell you that a mechanical fastener is far safer than a silicone adhesion.
 
Alright this is really bothering me. First of all if the plastic framed broke to begin with, it not that strong and you have to think why did it break? I would think it broke becuase of heat, A light that is putting out a lot of heat and casuing the plasting to continuously heat up and cool down and therefore causing it to fail in a short while. Aga uses plastic as a brace because its cheaper then using glass. If they were making a quaility product that was to last for ever then they would use glass for there supports, but they are out to make a profit like every other company. Most glass tanks have a strip of plastic around the edges to keep stupid people from cutting there self on the bare glass edge and chipping it when putting stuff in. It is not there for support unless there is a cross beam. Plastic is very weak compared to glass and silicone. Sure the mechanical fanster may seem safer then the silicone but after you fix it, the same thing will happen, the plastic will heat and cool and will eventuly fail to fatige agian. Now most of the AGA tanks that have center braces dont really need them. The plastic will give way before the glass and silicone.
 
Anyone want to take the frames off an All Glass aquarium and see how long it holds water? :D I would be curious to see if it would and for how long.
 
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